Weather A Concise Introduction

We now understand the basic mechanism behind condensation and the formation of dew: decrease the temperature until saturation is reached, and water vapor will start leaving the gas phase to form dew or frost. But what does it take for a cloud to form in the atmosphere? Why would the temperature decrease? What does water vapor condense upon in the absence of blades of grass and solid objects? In this chapter we will describe the cloud formation process and the conditions that are conducive to the formation of different types of clouds.